Furnace for roasting ores



(No Model.)

F. OB'RIEN. FURNACE FOR ROASTING ORES.

No. 464,103, PatentedDec. 1, 1891.

I UNITED STATES PATENT OFFICE.

FRANCIS OBRIEN, OF ELIZABETH, NEW JERSEY.

FURNACE FOR ROA STING ORE S.

SPECIFICATION forming part of Letters Patent No. 464,103, dated December 1, 1891..

Application filed July 22, 1889. Serial No- 318,226. (No model.)

To all whom it may concern.-

Be it known that I, FRANCIS OBRIEN, a citizen of the United States, residing at Elizaboth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Pyrites-Fnrnaces; and I do declare the following to be a full, clear, and exact description of the invention,

such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to furnaces for burn: ing pyrites ore, and has for its object the production of sulphurous acid. It consists in the construction and devices perfectly described whereby the ore is manipulated and the gases evolved therefrom during the process of roasting, all of which will be hereinafter more fully described and claimed.

Figure 1 is a perspective, and Fig. 2 a vertical longitudinal section, of a furnace constructed according to my invention. Fig. 3 is a horizontal section on line L y, Fig. 2.

The hearth A is inclined from its upper to its lower end, and underneath itI form a firepassage a, so it may be heated from end to end. I have not thought it necessary to show any form of fire-place or hearth,because the specific form of same does not enter into my invention and any desired form may be used. However, it may be well to state that the furnace or hot-air entrance is located at the end K and the heated gases and products of combustion pass through the said passage 0. in the direction of the arrows and escape into the stack indicated by the dotted lines L.

The calcining-chamber is divided into a series of retorts B, each one slightly lower than the one above it and all arranged in a gradually inclined plane, as will be understood most clearly from Fig. 2. The gas passage or flue C is arranged above this series of retorts and is connected with each of same by short ver-' tical fines b. At the upper end of passage 0 a suitable pipe D connects it with the acid chamber, of which illustration is not neces sary. tending the full width of the same I build projecting or deflecting guards b, which are On the rear side of the fines b and eX- inclined on their rear sides upward from the base of passage 0 to the line of the rear wall of the fines b. The object of these deflectors is to prevent the draft through passage 0 from entering the short fines b and .creating disturbance of the dust in the several retorts, as will be readily understood. The retorts B are supplied each with an Archimedean screw E, the shafts e of which are preferably made hollow and open to the atmosphere, as shown in Fig. 3, so as to prevent injurious overheating of said shafts. These shafts e have meshing gear-wheels F at their ends. The adjacent screws will be revolved in opposite directions, thus feeding the dust in the adjoining retorts toward opposite sides of the furnace. These several retorts B are con nected together by passages G, connecting the dischar e end of each retort with the receiving end of the one next below it.

A suitable hopper H is arranged to deliver the dust into the receiving end of the uppermost retort, and it is thence fed by means of the Archimedean screws through the several retorts until it is discharged at. h, at which point I prefer to use a door I, as shown in Fig. 1.

In practice I prefer to provide an opening J, leading into the lower end of the gas-passage C, so as to allow gas from other furnaces to be conducted through said passage in order to increase the heat to insure a more complete dcsulphurization of the ores.

When desired, a number of furnaces constructed as above may be connected so the gases evolved in one will serve to assist the others, or the furnaces may be used singly, as described. It will be noticed that by the arrangement of the retorts in an inclined plane the dust will be passed from one to the next lower one and is made to traverse all the retorts before it is finally discharged. Bythis construction and the location of the retorts on practically a roastinghearth, where they are heated approximately equally, I secure the burning of all the sulphur from the ores, as will be appreciated from the drawings and the descrip* tion before given.

Having thus described myinvention, whatI claim, and desire to secure by Letters Patent, 15*- 1. The herein-described furnace, having a gas-passage C and a series of connecting reends, a gas-passage arranged above'the said torts arranged in an inclined plane and proretorts, fiues connecting the retorts With the vided With Archimedean feed-screws and consaid passage and extending the full length of r 5 nected with the gas-passage by short flues, the said retorts, and feeders within the re 5 and the deflecting projections arranged on the torts to feed the ore in opposite directions in rear side of said short flues and extended into adjacent retorts, substantially as described. the gas chamber or passage, all substantially In testimony whereofI affix my signature in as and for the purposes set forth. presence of two Witnesses.

2. A furnace having an inclined roasting- FRANCIS OBRIEN. 1o hearth, a series of retorts arranged trans- Witnesses:

versely on the hearth and having the adja- JOHN T. DUNN,

cent retorts connected at alternate opposite WILLIAM R. PENN. 

